1. Field of the Invention
The present invention relates to a hammer type soil excavating machine which is used in a civil engineering and construction industry, and which can excavate a vertical hole, a horizontal hole or a diagonal hole easily, accurately and quickly.
2. Description of the Prior Art
Heretofore, as a tool for excavating a vertical hole or horizontal hole in the ground, there have been known, for example, a sword-type scoop or a semi circle-type scoop to which a handle is attached, and a device comprising two scoops facing each other wherein base portions of the two scoops are hinged, and handles are attached thereto.
And, as these scoops are operated by man power to excavate soil and sand, for example, when a deep hole is dug by the former, the surrounding of the hole is also dug so that the hole becomes a conical shape and unnecessary digging operation is involved.
Also, in the latter case, since the combination of the two scoops is operated by a lever attached to the handles to open and close, it is difficult to dig a hole of a depth of about one meter.
Further, in the hard ground, since it is impossible for the scoop to penetrate into the ground by man power, it has been dealt with a method such that stones and sand are broken down by a long iron bar and then taken out.
Furthermore, a vertical hole can be dug by the tools as mentioned above to a certain extent, but work is very difficult when a horizontal hole or a diagonal hole is dug at a narrow spot.
Also, a long digging time is required as well as a working posture of an operator is unstable, which imposes a burden on the operator and results in poor working efficiency.
Especially, lately, sewerage works often take place, and digging of a horizontal hole at a place where a machine drilling in a large scale cannot be conducted under the field condition becomes a factor of delaying the whole construction work, because such work relies on aged workers due to decrease of young workers who are engaged in the construction work, and the working efficiency is decreased therefor.